It is known to provide a container having two half shells which are joined together to receive a product. The half shells may be connected by a flap arrangement with one half shell interfitting with another.
Such receptacles are used as packaging for foodstuffs, e.g. in fast-food establishments. In the past such containers have been largely composed of foamed synthetic resin material and environmental concerns have been increasingly directed to such materials to the point that there is considerable interest in the development of more readily biodegradable packaging materials for such uses.
In particular, it has been suggested to use baked waffle-like starchy compositions as the material for such containers. However, such containers must be capable of retaining their shape, must be resistant to heat and must be reliably closable.
Furthermore, the container must be a mass-producible product of relatively low cost, easily manipulated, and capable of being utilized in the fast-food environment.
In a known device for accommodating meat products, a one-piece container has been provided with two half shells interconnected by a bent strip elastically. In another earlier construction, two separate half shells are provided with hook systems interengageable with one another and capable of being snapped together. When the half shells are, however, transported empty and are subjected to repeated opening and closing, the forms utilized for locking the half shells together tend to break off. As a consequence, these earlier systems were not fully satisfactory.
Austrian Patent 392 243 shows a two-shell container of readily biodegradable material which can be formed from densely baked waffle compositions predominantly of a starch base. The container halves are provided with locking elements along their edges to form a snap closure. This system cannot, however, withstand substantial loading.